Snowplow



Aug. 25, 1931. A. B. MOEN ET AL 1,820,707

I SNOWPLOW Filed June 25, 1928 3 Sheets-Sheet 1 Aug. 25, 1931. A. B. MOEN ET AL 1,820,707

SNOWPLOW Filed June 25, 1928 3 Sheets-Sheet 2 Aug. 25, 1931. A. B. MOEN ET AL SNOWPLOW Filed Jun 25, 1928 a Shets-Sheet s Patented Aug. 25, 1931 UNITED STATES PATENT OFFICE ANVER. B. MOEN, OF ST. JAMES, AND SYVER LIEN, OF COMFREY, MIFI'NESOTA SNOWPLOW Application filed .Tune 25,

This invention relates to snow plows and particularly to snow plows adapted to be mounted on a vehicle for clearing roads and streets.

It is an object of this invention to provide a novel and improved snow plow which is capable of being etfectivelyused for clearing packed or hardened snow and ice' from highways, and it is the further ob ect to provide such a plow which .will not only clear the snow and ice close to the ground, but will also clear the, same at. considerable height from the ground. 7

To these ends, the invention consists in the novel parts and novel combinations of parts hereinafter defined in the claims, and described in the following'specification made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the various views and, in which, I

Fig. 1 is a view in side elevation illustrating a snow plow embodying the present inventionapplied to the forward end of a tractor, certain of the parts being illustrated in full lines in one position and in dotted lines in another position;

Fig. 2 is a plan view trated in Fig. 1; I

Fig. 3 is a view in front elevation thereof; Fig. 4 is a more or less illustrative view in vertical section taken on the line 4.4 of Fig.

2, as is indicated by the arrows, and

Fig. 5 is a vertical section taken through the blower casing on the line 55 of Fig. 1,

as is indicated by the arrows.

Referring to the drawlngs, portions of a tractor A are illustrated including the 1'adiator 6, front axle 7, front wheels 8 and a power drive-oil shaft 9 extending longitudinally of the tractor and projecting to a point adjacent the forward end of the same.

In accordance with the present invention, a suitable frame work is provided for supporting the various parts of the plow, and this frame work may be pivotally secured, as illustrated, to small bars 10 fixed to the front axle 7 of the tractor by U-clips 11.. The

of the snow plow illusframe work includes a pair of-bars 12 which are pivoted to the short bars 10 and which 1928. Serial No. 287,944.

curve downwardly therefrom and extend forwardly, and are secured at their forward ends to the lower side of a mold board 13 which,. in turn, extends transversely respective to the tractor A well forward of the same. Bars 12 adjacent their forward ends also support a blower casing 14 to which the central portion of the mold board 13 is secured. The frame work also includes a U-shaped bar 15 which is substantially vertically disposed '60 and the lower ends of which project up-' wardly from adjacent the rear ends of the bars 12. Projecting diagonally outwardly from the lower ends of the U-shaped bar 15, arms 16 are provided and the forward portions of said arms are bent so that the two arms will extend in parallel relationship adjacent the ends of the mold board 13. Chains 17 secured to the arms 16 adjacent their forward ends, project upwardly and are fixed to the upper portions of the U-shaped bar 15. The whole frame work and the parts carried thereby, can be raised or lowered by means of a block and tackle 18 which is secured to the central portion of the U-shaped bar 15 and extends rearwardly therefrom, to be secured to its rear end as to the rear end of the traci tor (not illustrated). Forwardly from the lower ends of the chain 17, vertical arms 19 are secured to the arms 16 and project upwardly therefrom. Extensions 20 of the arms '19 run forwardly and upwardly from the upper ends of the arms 19 and have secured thereto, a transverse shield 21 which extends upwardly and forwardly from the upper edge of the mold board 13, as a continuation thereof. In addition to'the bars 12, arms 16, arms 19, extensions 20 and U-shaped bar 15, the frame work for supporting the various parts of the plow includes suitable transverse bars 22 and 23 which extend between the arms 16 immediately forwardly of the U-shaped bar 15 and immediately behind the blower casing 14 respectively. Transverse bars 22 and 28 are adapted to support suitable bearings within which the various shafts, to be hereinafterYmentioned, are journaled.

The mold board 13 is of considerably greater width than the width of the tractor upon which the plow is supported, and the lower edge of the mold board projects downwardly to adjacent the ground. The mold board is of trough shape and is almost semicylindrical in vertical cross section and the upper edge of the mold board projects forwardlv some little distance ahead of the lower edge thereof, and is joined to the shield 21. The shield 21, in reality. is a continuation of the mold board and projects first upwardly and is then curved upwardly and forwardly in an arc of a circle, so that the upper edge of the shield 21 projects quite a distance above and forward of the upper edge of the mold board 13. The blower casing 14 is of substantially cylindrical shape, extends Vertically and is provided with a tangential discharge port 14a. As stated, the mold board is secured to the blower casing and abuts the forward side thereof, and the mold board is provided adjacent its upper central portion with an opening, and a casing 24 forms a passage from the opening in the mold board to a central intake opening in the forward side of the blower casing. Suitably journaled in the forward ends of the arms 16 of the frame work is a square lower disintegrator shaft 25 and this shaft projects outwardly a short distance beyond the arms 16. The shaft 25 is so disposed relative to the mold board 13, that the surface of the mold board in vertical cross section will form the arc of a circle drawn about the center of the shaft 25 Mounted on the shaft 25 and extending inwardly to points adjacent the central opening in the mold board are a plurality of spaced disintegrator blades 26. Each of these blades is constructed from an oblong metal bar and has a square opening through its central portion through which the shaft 25 fits. The shaft 25 is adapted to rotate in a clockwise direction, as viewed in Fig. 1 and as indicated by the arrow. The blades 26 outwardly from ,their central portions are twisted to have their forward edges spaced a greater distance from the horizontal center of the shaft 25 than their rear edges. The various blades are held in spaced arrangement from each other as by spacing collars 27, and successively inwardly spaced blades 27 are circumferentially spaced relative to the axial center of the shaft 27, so that successively inwardly spaced blades will act behind successively outwardly spaced blades. The number of the blades 26 used, and the amount of twist of the blades relative to the shaft 25 and the circumferentialspacing of successively inwardly spaced blades 25 relative to successively outwardly spaced blades on the shaft 25 may be varied as desired. The object of this particular construction is to provide blades having angular cutting surfaces at their ends, which will chop and cut snow and ice adjacent the ground; and as the snow and ice is chopped and cut, it will be carried inwardly from one blade to a next inwardly spaced blade toward the center of the mold board and the various blades will, progressively act on the snow and ice, to carry the same to the center of the mold board. At the center of the shaft 25 opposite the opening in the mold board, a different type of disintegrator blade is mounted on the shaft. Preferably four or more of these blades 28 are used and they may be termed ejector disin tegrator blades. The blades 28, like the blades 27, are formed from oblong bars and are provided at their central portions with square openings through which the shaft 25 extends, and the various blades are spaced from each other on the shaft by means of spacing collars 27. The blades 28, however, outwardly from their central portions are twisted at right angles so that the wide portions of the outer edges of the blades extend parallel to the shaft 25. The wide portions of the blades will, therefore, extend normal to the direction of rotation of the blades and the blades will,.therefore, act as paddles to pick up the snow carried to the central portion ofthe mold board by the blades 26, and throw the snow into the opening through the mold board into the blower casing 14.

Centrally journaled in the rear portion of the blower casing 14 is ablower shaft 29, and this shaft projects rearwardly from the blower casing and is journaled in suitable bearings 30 mounted on the cross bars 22 and 23. The blower shaft 29 projects forwardly into the blower casing and carries at its forward end a conical support 31 to which is secured a conical blower member 32. The shaft 29 is centrally disposed relative to the opening through the forward side of the blower casing and the base of the conical member 32 extends rearwardly. Secured to the conical member 32 and projecting forwardly therefrom, are a plurality of triangular blades 33 having flanges bolted to the conical member 32, and the blades 33 of the blower are so disposed that they extend tangentially respective to a circle which might be formed by truncating the conical member 32 slightly rearwardly from its forward pointed end. The blower will receive the snow and ice from the ejecting blades 28 of the lower disintegrator and the blower will also act to suck in the snow into the blower casing, whereupon the snow striking the conical member 32 will be carried to the outer side thereof, by centrifugal force and will be caught by the blades 33 of the blower and carried upwardly and outwardly into the discharge port 14a of the blower casing. Secured to the upper end of the discharge port 14a is a ring 34 of angular shape in cross section and the ring is so secured to the outer side of the port 14a that one flange of the ring will extend horizontally and flush with the upper edge of the port 14a, and this horizontal flange will be provided with a the arm 37 may outwardly in a wide arc,

series of inwardly projecting circumferentially spaced notches 34a. A discharge hood 35 is mounted at the upper end of the discharge port 14a of the blower casing and this hood has its upper side curved upwardly and and the hood is diagonally cut to the vertical at its discharged end. A ring 36 of angular shape in cross section is secured to the lower end of the hood 35 and one flange of the ring projects horizontally from the hood and flush with the lower end of the hood, so that the horizontal flange rests directly upon the horizontal flange of the ring 34. Amanipulating arm 37 is pivoted at its upper end to the vertical flange of the ring. 36 and immediately below the point of pivotal attachment to the ring 36 the horizontal flange of the ring is cut away to form a notch within which the arm 37 is adapted to fit when the arm is downwardly swung. Several hook brackets 34b fixed to ring 34 fit over the horizontal flange of ring 36 and form, with the horizontal flange of ring 34, a bearing within which hood 35 may be rotated. It will be seen from an inspection of Fig. 1, of the drawings, that be raised from downwardly extending vertical position upwardly to horizontal position, whereupon by rotating the arm 37, the hood 35 may be rotated until the arm is in alinement with one of the notches 34a, and then the arm 37 may be downwardly swung to engage in the alined notch 34a to securely hold the hood from rotation. The hood 35 may, accordingly, be adjusted to cause the same to discharge at either side of the machine at various angular positions relative to the axis of rotation of the hood.

A shaft 38 is journaled in the upper ends of the arms 19 of the frame work, so that it extends transversely of the plow and this shaft carries adjacent each end and slightly outwardly from the sides of the shield 21, the two bars 39 which project forwardly for some distance beyond the shield 21 and have journaled in their forward ends a square upper disintegrator shaft 40, which extends forward of the lower disintegrator shaft 25 and considerably above the same. Mounted on the upper disintegrator shaft are a plurality of upper disintegrator blades 41 which are made in rights and lefts. The blades 41 are preferably constructed from an oblong bar of metal and are provided at their central portion with a square opening through which the shaft 40 extends and from portion each blade projects straight outwardly in both directions for some considerable distance, whereupon the two ends of the bar are twisted slightly and bent so'as to form scoop-like arms. The upper disintegrator shaft as illustrated by the arrow, Fig. 1, will rotate in a clockwise direction in the same manner as the lower disintegrator shaft 35.

.et 50, secured to the their central 7 Accordingly, the various scoop portions of the blades 41 are bent so that they extend inwardly towards the center of the shaft 38, and the rear edges of the scoop portions due to the twists are given a greater angular bend than the forward edges, so that as the blades 41 strike snow and ice they will chop the same up and will move the same centrally and downwardly to the lower disintegrator. The various blades 41 are spaced from each other on the shaft 40 by means of the spacing collars 42 andthe blades are so set relative to each other that successively inwardly spaced blades will follow in their action on the snow the successively outwardly spaced blades. bu that snow engaged by outwardly spaced blades, if not carried all the way downwardly to the lower disintegrator, will be moved centrally of the plow a sufiicient distance so that the successively inwardly spaced blades will pick the same up and continuethe in ward and downward movement. Preferably, short brace bars 43 are used which extend between .and connect the upper ends of the arm:-: 19 to the corners formed between the upper edges of the mold board 13 and the lower edge of the shield 21. Also a brace plate 44 is preferably used adjacent the lower edge of the mold board 13 which extends throughout the length of the mold board, to strengthen the lower edge of the same.

The power take-off shaft 9 from the tractor carries a pin 45 adjacent its outer end and a sleeve coupling 46 having slots in either side through which the pin 45 fits, is loosely mounted on the outer end of the shaft 9. Thesleeve 46 is, accordingly, extensible outwardly or inwardly versal joint 47 connects the sleeve 46 to a main from the shaft 9. A unidrive shaft 48 for the snow plow and the main drive shaft is suitably journaled in a. bearing bracket 49 secured to the cross bar 22 adjacent one end thereof, and centrally upstanding therefrom. Due to the universal joint 47 and the extensible sleeve 45, it will be seen that the frame work and the various parts of the plow supported thereon can be raised or lowered respective to the tractor and yet the power can be applied from the shaft 9 to the main drive shaft 48. A sprockforward end of the main drive shaft 48, drives the blower shaft 29 through a. sprocket chain 51 and a sprocket 52 fixed to the blower shaft. A beveled gear 53, fixed to the blower shaft 29, meshes with a beveled gear 54 secured to the inner end of a counter shaft 55 which extends transversely of the plow outwardly to one side thereof, from adjacent the center, and is suitably j ournaled in a bearing bracket 56 fixed to and upstanding from the forward transverse bar 23 and in a rearward extension 57 projecting from the forward end of one of the arms 16. Adjacent its outer end, the shaft 55 carries a sprocket 58 and a sprocket 59 is mounted on the lower disintegrator shaft 25 outwardly from the arms 16 and adjacent one of the outer ends of the shaft 25. The lower disintegrator shaft 25 is driven from the counter shaft 55 by means of a sprocket chain 60 which runs over the two sprocket wheels 58 and 59. The counter shaft 55, at its outer end, carries a sprocket 61, and a sprocket 62. journaled on the counter shaft 38 is driven from the sprocket 61 by means of a sprocket chain 63. The sprocket 62 is secured to .a second sprocket 64 which is also journaled on the counter shaft 38, and the upper disintegrator shaft 40 is driven from the sprocket 64 by means of a sprocket chain 65 running over the sprocket 64 and over a sprocket 66 mounted adjacent one end of the upper disintegrator shaft 40 outwardly from an arm With this construction, it will be observed that the arms 39, within which the upper disintegrator shaft 40 is journaled, may be swung upwardly and downwardly and yet power may be applied to the upper disintegrator shaft.

Mounted on the main drive shaft 48 of the snow plow adjacent its forward end is a sprocket 67 and this sprocket is adapted to drive through a sprocket chain 68 on to a sprocket 69 journaled on a longitudinal shaft 70 journaled in suitable bearing brackets 700, secured to and projecting upwardly from the cross bars 22 and 23 respectively, adjacent the opposite ends of the bars from the drive mechanism for the upper and lower disintegra or shaft. The sprocket 69 on the longitudinal shaft 70 carries a half clutch member 71, which is rotatable therewith but slidable thereon, to be engaged with a second half clutch member 72 fixed to the shaft 70. The half clutch member 71 has a shifting head formed integral therewith and the clutch is adapted to be shifted by a shift lever 73 pivotally mounted on a suitable support extending upwardly from the right arm 16. The shift lever 73 is adapted to be controlled by a wire or cord 74 which extends rearwardly from the outer end of the shift lever and is adapted to be controlled by the driver of the tractor. Aworm 75 is fixed to the shaft 70 adjacent its forward end, and is in mesh with a worm gear 76, carried on a short transverse shaft 77, journaled in suitable bearings 78 and mounted adjacent the right end of the forward cross bar 23 of the frame work, as is best seen in Fig. 2 of the drawings. The short shaft 77 carries at its outer end a crank 7 9. which is pivoted to a link 79a and-this link, in turn, is pivotally connected to an arm 80 fixed at its forward end to the transverse shaft 38. When the snow plow is being driven and the clutch, including the half clutch members 71 and 72 and the shift lever 7 3', is thrown into engage ment, crank 79 will be rotated to oscillate the shaft 38 which, in turn, will swing the arms 39 carrying the upper disintegrator shaft 40 upwardly and downwardly, thereby causing the upper disintegrator to be intermittently raised and lowered, as from a position illustrated in full lines Fig.1 to the position illustrated in dotted lines Fig. 1. The shield 21 is so constructed that it will not interfere with the upward and downward movement ofthe upper disintegrator. Due to the fact that the short shaft 77 is driven through the worm 75 and worm gear 76, it will be seen that the rotation of this shaft 72 will be very slow in comparison tothe rotation of most of the other parts of the plow. Accordingly, the oscillatory movement of the upper disintcgrator will be quite slow and gradual.

Mounted at either end of the lower dis integrator shaft 25 are cutter blades 81 and these blades are constructed in the same manner as the outer disintegrator blades 26 of the lower disintegrator. They will act to cut away snow and ice ahead of the disintegrator shaft 25 and ahead of certain of the various sprockets and sprocket chains. They will thus act to permit a free passage of the sides of the plow through the snow during its forward travel. Mounted at either end of the upper disintegrator shaft 40 are cutter blades 82 which are constructed like the cutter blades 81, with the exception that they are of shorter length. The cutter blades 82 will act like the cutter blades 81, to permit a free passage of the upper portion of the sides of the plow and of the various sprockets and sprocket chains through the high snow.

Operation will be actuated to drive the blower-through the sprocket 50, sprocket chain 51, sprocket 52 and blower shaft 29. The lower disintegrator will be driven off the blower shaft 29 through the beveled gears 53 and 54, shaft 55, sprocket 58, sprocket chain 60 and sprocket 59. The upper disintegrator will lbedriven from the shaft55 by the sprocket 61, sprocket chains 63, sprockets 62 and 64, sprocket chain 65 and sprocket 66. When the clutch is in engagement, the short shaft 77 will be driven from the main drive shaft 48 through the sprocket 67, sprocket chain 68, sprocket 69, half clutch members 71 and 72, shaft 70, worm 75 and worm gear 76 and the upper disintegrator will be oscillated from motion imported thereto from the crank 79 secured to the shaft 77, link 79a and the arm 80. The lower disintegrator will act ahead of the mold board 13 and adjacent the ground to break up and convey the snow and blowing.

ice to the center of the mold board and to force the same into the blower casing 14. The outer blades of the lower disintegrator will chop up the ice and snow adjacent the ground, and will convey the same inwardly to the central ejecting blades 28 which will throw the snow and ice into the passage from the mold board to the blower casing. The upper disintegrator will move slowly upwardly and downwardly during the travel of the plow and will chop, scoop up and convey snow downwardly and centrally to the lower disintegrator. As during its oscillatory movement, the upper disintegrator will raise to a considerable height, it will be seen that snow at a high level, such as is found in huge drifts, may be removed from the road. If it is desired to maintain the upper disintegrator at a certain determined level. the operator of the tractor may move the operating cord or wire 74 to move the half clutch members 71 and 72 out of engagement, thereby causing the upper disintegrator to remain at a constant desired level.

As snow and ice is discharged into the .passage between the mold board and the blower casing, the blower will suck the same into the casing, and the blades 33 co-operating with the conical member 32 ,will carry the snow upwardly into the discharge port 14a, where it will be directed outwardly to one side of the road by the hood 35. As a general rule, it will be found advantageous to discharge snow in the direction in which the wind is By operating the arm 37, and swinging the hood 35, the snow may be dis charged in any desired direction.

If it is desired to raise the whole snow plow from the road, as when the same is being brought to or from the point where it is to be used the block and tackle 18 may be operated to swing the frame work and the parts of the plow upwardly.

The device has been demonstrated in actual practice and has been found to be very efficient for the purposes intended. It is found particularly effective for clearing packed and partially iced snow from city streets, due to the chopping action of the blades of the lower disintegrator which act adjacent the ground. Hereto helical screw type conveyors have been used in clearing snow, but it is found that this type of conveyors cannot be used effectively where the snow has been packed down or has partially melted and then frozen, due to the fact that no chopping action is obtained with, the helical conveyors. The present device effectively clears such ice'and snow.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of the present invention.

larly respective to said shaft, and said blades being respectively seton said shaft so that successively inwardly spaced blades will pick up the snow and ice acted on by successively outwardly spaced blades and convey the same towards the center of said mold board, ejecting means suitably mounted and having communication with the central portion of said mold board and adapted to eject the snow at one side of the plow, and a plurality of disintegrator blades mounted centrally on said disintegrator shaft and having their outer ends bent parallel with said shaft to throw the centrally conveyed snow into said ejecting means.

2. A snow plow adapted to be mounted on a vehicle, having in combination, a mold board, means for engaging snow ahead of said mold board and moving the same centrally therein, ejecting means in communication with the central portion of said mold board and to which said means is adapted to deliver, and an upper disintegrating and conveying means disposed above said first mentioned means and comprising a shaft, means for rotating said shaft and a plurality of arms mounted on said shaft and having their outer ends formed as scoops, successively inwardly spaced arms being circumferentially spaced on said shaftrelative to successively outwardly spaced arms so that the inwardly spaced arms will follow in their action on the snow, the outwardly spaced arms to break up and convey the snow above said first mentioned means downwardly and centrally thereto.

3. The structure defined in claim 2, and means for oscillating said upper distintegrating and conveying means upwardly and downwardly relative to said first mentioned means during the travel of the plow, to break up and convey snow at various heights above said first mentioned means.

4. A snow plow adapted to be mounted on a vehicle having in combination, supporting means adapted to be secured to the forward end of a vehicle, a mold board secured to said supporting means to extend transversely of the-vehicle, a shield secured to the upper end of said mold board and projecting upwardly and forwardly therefrom, a rotary ejecting means secured to and communicating with the central portion of said mold board, a lower rotary disintegrator journaled in said frame, working ahead of member mounted in a swingable frame for upwardly and downwardly oscillatory movement ahead of said shield above said lower disintegrating means and adapted to engage,

.break up and centrally convey snow and ice above said lower disintegrating means downwardly thereto, means for rotating said two disintegrating means and means for oscillating said upper disintegrator upwardly and downwardly.

5. A snow plow adapted to be mounted on a vehicle and having in combination, a suitable supporting frame, ejecting means mounted on said frame, a mold board secured transversely of said frame, a dismtegrator shaft j ournaled in said frame ahead of said mold board, disintegrating and conveying means mounted on said shaft for breaking up and conveying snow and ice centrally of said mold board to said e ectlng means, and cutter blades mounted at the outer ends of said shaft for cutting away snow 1n the path of said shaft and frame and for conveying the snow transversely thereof.

6. The structure defined in claim 5, an upper disintegrator shaft journaled in said frame above said first mentioned shaft and ahead of the same, disintegrating and conveying means mounted on said upper shaft for breaking up and conveying snow above said first mentioned disintegrating and conveying means downwardly and centrally thereto, and cutter blades mounted at the outer ends of said second mentioned shaft for cutting away snow in the path of said second mentioned shaft and said frame and for conveying the snow transversely thereof.

7. A snow plow adapted to be mounted on a vehicle and having in combination, a suitable sunporting frame, a drive shaft suitably journaled in said frame and adapted to be driven from a power shaft of the vehicle, a mold board secured transverselv of said frame at the forward end thereof, a rotary ejecting means in communication with the central portion of said mold board and adapted to be driven ofl said main drive shaft, a lower disintegrating and conveying means mounted forward of said mold board and adapted to be driven off said drive shaft for rotation in close contact with the ground to break up and convey snow and ice adjacent the ground centrally of said mold board to said ejecting means, an upper disintegrating and conveying means mounted above and for ward of said lower disintegrator means and adapted to be driven off said main drive shaft for rotation above the path of said lower disintegrating means to break up and convey the snow dmvmvardly thereto, means adapted to be driven off said main drive shaft for oscillating said upper disintegrating and conveying means upwardly and downwardly during travel of the plow, and means for throwing said last mentioned means out of engagement to hold said upper disintegrating and conveying means at a desired level above said lower disintegrating and conveying means.

8. The combination with a rotary snow ejecting fan having a vertical outlet port, of a horizontally disposed flanged ring secured to the upper end of said port and projecting outwardly therefrom, the flange of said ring having a plurality of radial notches out therein, a hood mounted on the upper end of said port and bearing against said ring for rotation about a vertical axis in respect thereto, and an arm pivoted at one end to the lower end of said hood and adapted to be used when swung upwardly for turning said hood respective to said port and adapted to be swung downwardly to engage in one of said notches to hold said hood from rotation relative to said port.

- 9. A snow plow adapted to be mounted on a vehicle, having in combination a mold board, ejecting means behind said mold board adapted to receive and eject material collected by said mold board, a shield above said mold board extending upwardly and forwardly therefrom, an auxiliary frame including swingable supporting members, the outer ends of which are disposed on the forward side of said shield, a rotary disintegrating and conveying member mounted in said swingable frame, driving means for said disintegrating member, and means for oscillating said frame to move the same up and down across said shield.

10. A snow plow adapted to be mounted on a vehicle having in combination a mold board, a rotary disintegrating and conveying member working in said mold board aheadof the same and provided with a series of circumferentially staggered and radially extending breaker'elements adapted to break up snow and ice adjacent the ground and to move the dislntegrated material centrally from the ends of said breaker member, and a second rotary disintegrating and conveying member working in association with said first disintegrating member and mounted above and forward of said first disintegrator, said last mentioned disintegrator also havingcircumferentially staggered disintegrating elements adapted to break up material and convey the disintegrated materialcentrally and downwardly to said mold board.

11. The structure set forth in claim 10, a swingable bracket in which said second disintegrator is rotatably mounted, means for driving said second disintegrator, means for 

